Machine for producing sliding clasp fasteners



July 23, 1,957 F. 'MULKA 2, 0

MACHINE FOR PRODUCING SLIDING cusp FASTENERS Filed Nov. 23, 1953 INVFNMP7 7 1 Na/lra Arm tates nite MACHINE FOR PRODUCING SLIDING CLASPFASTENERS The present invention relates to sliding clasp fasteners, andmore particularly to a fully automaticmachine for the production of asliding clasp fastener with elements embedded in cloth folds and clipsgripping from the outer side.

This type of sliding clasp fastener is known and the invention relatesto a fully automatic machine for making this type of fastener which isthe latest known to the art.

Different kinds of automatic machines are already known for settingsliding clasp elements on cloth bands or stringers. But there exists nomachine which is capable of producing the above mentioned novel type ofsliding clasp fastener.

Moreover, the constructional parts already known in technical designingare not sufiicient to enable the building of a suitable machine on thegeneral technical lines applicable to the particular branch ofengineering. Consequently the problem to be solved required inventiveingenuity. r

A preferred embodiment of the invention is hereinafter described withreference to the accompanying drawing, in which:

Fig. 1 shows a new sliding clasp fastener in cross section;

Fig. 1a is a vertical cross section taken at right angles to that ofFig. 1; v

Fig. 2 shows diagrammatically in top plan view 'the essential parts forproducing thefastener illustrated in Fig. l;

Fig. 3 is also a diagrammatic view of Fig. 2 in side elevation, partlyin longitudinal section.

Fig. 3a is a vertical section taken on the lines of Fig. 3;

Fig. 3b is a similar section taken through the left hand ends of plates27, 28;

Fig. 4a is a detail partly in section showing one mode of supporting theclips being fed to the assembly point;

Fig. 4b is a detail partly in section showing the relation of the partsat the assembly point;

Fig. 4c is a similar view showing the parts in clipclosing position, andshowing the arrangement of the web-cutter 23, which is located one stepbeyond the assembly point as shown in Fig. 3.

atent 0 ice Figs. 1 and 3. clips are V-shaped. The jaws 11, after beingacted upon by the lifts 6, can be moved apart by tension or compressionsprings (not shown). Before the clips 1 are pressed together the studs 2and the cloth band or stringer 3 are introduced into the clip in thefollowing manner:

The cam 8 acts on a control rod 17 which has a groove set at an angle ofabout 45 in which a pin or roller 18 engages. As the rod 17 moves to andfro the horizontal movement is converted by the groove into a verticalmovement which is imparted to a control rod 19. A

strap 20 carried by the rod 19 is connected to a ram Fig. 4d is avertical sectional detail showing one mode I of supporting the studs formovement by pawl 16 to position 2a of Fig. 3, and for providing fortheir downward displacement by the ram 25.

Referring to Fig. l, studs 2 are fixed in the fold of a cloth band 3 byclips 1 gripping from the outside. In the machine illustrated a drivingshaft 4 carries a cam disk 5. This'disk has lifts or curves 6, 7 and 8.The lifts 6, which are mutually displaced through an angle of 180, actsimultaneously and alternately on ends 9a of two similarly shaped levers9. These levers turn about their pivots 1t) and their other ends .act onspreader jaws 11. These jaws serve for clamping the clips fed in theform of a chain formed by webs 1a as shown in p by a pin 24. As the ramdescends it pushes a stud 2a into the clip 1 located thereunder andwhich has not yet been compressed. The cloth strip 3 which is under thestud 2a (Fig. 3,) is simultaneously pressed in so that after the jaws 11have'operated the result shown in Fig. 1 is attained.

A plate 27 serves as guide for the studs 2 which are also fed likeachain. The row of studs is of course supported against movementlaterally of the intended direction of feed by the lateral faces ofguiding tracks (27a) adapted to their cross section. The plate 27therefore does not have, efiectively, a plane surface, but effectivelyaffords a guiding groove or channel as illustrated in Fig. 30:. Supportand guidance is of course also afforded in a similar manner for the rowof clips 1,. as illustrated at 112 in Fig. 4a. A plate 28 and the plate27 form a guide for the cloth band or stringer 3 as shown in Fig. 3, andthe, clips 1 cannot be forced upwardly from their guiding support underpressure of the pawl 21, as such displacement is prevented by theunderside of the guide-plate 28.- As indicated 'at the left indiagrammatic Fig. 3 (see also Fig.3b), the plates 27 and 28v are cutaway at their ends 27b, 28b underlying the ram 25 so that as illustratedin Fig. 4b the ram, carrying one of the studs 2a, may descend, pushingthe tape 3 ahead of it, into the underlying clip 1 which is then closedaround the tape and the base of the stud by the jawsll as shown in Fig.4c. The supporting plate for the clip 1 of course extends under the jaws11 and the ram 25 and dog 21 hold the thus supported clip in placethereon while it is being closed. The stud positioning end of the ram,shown as of sheet like form in Fig. 3, of course is as narrow as, ornarrower than, the shank of the stud 2 (Fig. 1) and thus can carry thestud 2a into position to have the clip 1 closed about the fold in thestrip 3 embracing its foot, and still be withdrawn after the clip hasbeen closed (cf. Figs. 4b and 4c). For diagrammatic clarity, Fig. 3shows the tape 3 as initially inserted and before it has been depressedinto the clip 1, shows the row of clips 1 as extending past the cut olfposition 23, and shows the stud 2a. in the position from which it isstruck down by the ram 25. It will be appreciated that with the machineoperating at the rate hereinafter mentioned, the effect of gravity onthe stud 2a is negligible as compared to the movements positivelyenforced on the parts, and that in operation of the machine, the tape 3,and previously set studs, are actually locked in the clips located tothe left of the ram portion. It will also be appreciated that theleading tine of the ram 25 (at the left of stud 2a, Fig. .3) entersbetween the tape embraced by the sides of the previously set clip'andthat being closed, and thus assists in supporting the clips while theyare being severed by the punch 23, as hereinafter described. Forrelatively slow operation any suitable means may be employed for guidingthe studs to, and supporting them at, the position 2a. For example, asshown in Fig. 4d, the stud heads may be supported between resilienttracks 212, from between which they may be forced by descent of the ram2 5,but such sup- Before being clamped or compressed the port is notessential when the machine operates at a high rate of speed. After theclips are severed by the punch 23, the strip 3 to which the studs andclips are attached, maintains the continuity of the fastener assembly,which feeds from theseverance point 23 over the underlying basepf. themachine (cross-hatched in Fig. 4b) until removed therefrom.

The clip chain is fed towards the leftlinkby link by means of the camlifts 7, a control rod 12 and a feed pawl 21 which is pivoted at 22, ascan be clearly seen fromFigs. 2 and 3. Similarly the stud chain is movedforward step by step by a horizontal pawl-13 pivoted at 15 and by an arm14 on the control rod 12.

. A particularly important feature of the invention is an additionalpawl 16 which is mounted on the pin 15 with the pawl 13. This additionalpawl moves each stud 20: into the position shown in Fig. 3 so that it isdeposited exactly inv the middle of one of theclips- 1, an operationwhichsmust. be carried out with the highest degreeof accuracy. In vFigs.2 and.3 the additional pawl 16 is shown by thin lines. Before theadditional pawl 16 becomes, operative the stud Zdis separated from thechain onthe plate 27 by a cutter 26 as shown in Fig. 3. This cutter. 26drops downwardly with the ram 25 until it reaches the position shown inFig. 3 resting on one of the little webs that initially connect thestuds 2 into a strip orchain. The downward motion of the cutter 26 then,cea'ses whilev motion of the ram 25 continues, for which purposeclearance isprovided as indicated by the lost motion space in ram 25adjacent the cutter arm 26 in Fig. 3. Finally, as the ram 25 approachesthe end of its downward stroke, the cutter 26 reaches the upper end ofthe lost motion space, and is thus driven through the little connectingweb as the ram 25 moves to the end of its downward stroke. 7

,Whenthe' st'ud 2a has been fixed, the clip 1 last compressed is severedbya punch 23. This punch is con-' trolled. by the jaws 11. ,Itwill'likewis'e be appreciated that these jaws, closing onthe followingclip 1, further aid in immobilizing the connection 1a being severed bythe punch, 23,v which, in the form shown is carried by and moves withone of said jaws (see Fig. 2). The pressure required by the: pawls '13,and 21 can be produced in known manner by springs. v p The idea of theinvention is the automatic feed of the two chains 1 and 2 and thesevering'of the studs 2a before theyare introduced and the severance ofthe clips 1 at 1a,,after the studs 2a have been fixed or clamped inposition.

From a kinematic point 'of view the whole mechanism represents a novel.technical advance in the art. For example during. a single revolution ofthe driving shaft 4 two working operations take place, namely theclamping of the studs and the feeding of chains 1 and 2 and of the clothband orstringer 3. g

The actions of force of the levers 9 are oppositely directed and the oneoffsets the other in relation to the driving shaft 4, The mechanismtherefore, even when the driving shaft 4 is running at maximum speed,say about 1400 revolutions per minute, is dynamically balanced. As allmovements are derived from a single driving shaft with the aid of camsor lifts, they can be carried out in the best possible manner accordingto the rules of kinematics and dynamics. The movements can be producedby cams and races having the smallest pitch, beginning at zero andending at zero.

It will, of course, be understood that various details of constructionmay be varied through a wide range without departing from the principlesof this invention and it is, therefore, not the purpose to limit thepatent granted hereon otherwise than necessitated by the scope of theappended claims.

I claim: I

1. An automatic machine for the production of a sliding clasp fastenerof the type formed by assembling studs within a folded flexible stripand gripping the same therein by clips clamped externally about thefold, said machine comprising, in combination, means for guiding theflexible strip past an assembly point, means for feeding a chain ofopen-jawed clip elements to said assembly point with their open jawsfacing one side of said strip at said assembly point, means for feedinga chain of stud elements toward said assembly point on the other side ofsaid strip, meansfor severing the leading stud element from the chain ofstud elements, means for advan'cing the severed stud element to aposition aligned with the open jaws of a clip element at the assemblypoint with said strip intervening therebetween, for forcing the soaligned stud element against the strip, and for forcing said studelement and said intervening portion of said strip into the alignedopen-jawed clip thus placing said stud element in a fold in said stripmeans for closing the jaws of the said clip to thereby afiix the alignedstud and clip to the folded strip, and means for severing the closedclip from the chain of clips.

2. An automatic machine for the production of a sliding clasp fastenerof the type formed by assembling studs Within a folded flexible stripand gripping the same therein by clips clamped externally about thefold, said machine comprising, in cor'nbination, means for guiding theflexible strip past an assembly point, means for feeding a chain ofopen-jawed clip elements to said assembly point step by step with theiropen jaws facing one side of said strip, at said assembly point, meansfor feeding a chain of stud elements toward said assembly point on theother side of said strip, means for severing the leading stud elementfrom the chain of stud elements, means for advancing the severed studelement to a position aligned withthe open jaws of a clip element at theassembly point with said strip intervening therebetween, for forcing theso aligned stud element against the strip, and for forcing said studelement and said intervening portion of said strip into the alignedopen-jawed clip thus placing said stud element in -a fold in said strip,reciprocating means for closing the jaws of the said clip to therebyaflix the aligned stud and clip to the folded strip, and means forsevering the closed clip from the chain of clips.

3. An automatic machine for the production of a sliding clasp fastenerof the type formed by assembling studs within a folded flexible stripand gripping the same therein by clips clamped externally about thefold, said machine comprising, in combination, means for guiding theflexiblestrip past an assembly point, reciprocating means for feeding achain of open-jawed clip elements to said assembly point step by stepwith their open jaws facing one side of said strip at said assemblypoint, means for feeding a chain of'stu'd elements toward said assemblypoint on the other side of said strip, means for severing the leadingstud element from the chain of stud elements, reciprocating means foradvancing the severed stud element to a position aligned with the, openjaws of a clip element at the assembly point with'said strip interveningtherebetween, for forcing the so aligned stud element against the strip,and for forcing said studelement and said intervening portion of saidstrip into the aligned open-jawed clip thus placing said stud element ina fold in said strip reciprocating' means for closing the jaws of thesaid clip to thereby affix the aligned stud and clip to the foldedstrip, and means for severing the closed clip from the chain of clips. v

4. An automatic machine according to claim 3, said machine having avertical driving shaft, said shaft carrying cam discs for actuating saidreciprocating clip feeding and stud advancing mea'ns, said cam discs andsaid reciprocatingclip feeding and stud advancing means beinghorizontally oriented, whereby the reciprocatioiis thereof take place atright angles to the force of gravity and are free of gravityaccelerations and decelerations.

5. A machine according to claim 1, said jaw closing means being arrangedto close a clip while said clip is still attached to said chain ofclips, and said clip severing means being arranged to sever and clipfrom the chain at a position removed from the point at which said clipis closed.

References Cited in the file of this patent UNITED STATES PATENTS KaseSept. 22, 1936 Legat Apr. 23, 1940 Norkin et a1. Oct. 2, 1945 AndrenMar. 20, 1951 Mackey Mar. 2, 1954

